mmmhhhh!
I would say DGS (German Sign language) is the one, I feel more easier with because I use it for a long time. DGS with A to Z is the almost similar as
ASL but bit different with "SCH", ö, ä, ü, ß, mm, nn. DGS, BSL, ASL & Korean sign languages are total different.
BSL (British sign language) with A to Z = use with 2 hands - comfortable to use sign languages. I would use it when I am in England.
The Korean sign languages are total complication than all but it took me few months to familiar with those sign languages but with A-Z is total
umpossible.... I can´t do it but only sign languages.
I prefer both BSL & DGS because I use them mostly than ASL.
:P